unreasonable

adjective

un·rea·son·able

ˌən-ˈrēz-nə-bəl,

-ˈrē-zᵊn-ə-bəl

Synonyms of unreasonable

: not governed by or acting according to reason

unreasonable people

: not conformable to reason : absurd

unreasonable beliefs

: exceeding the bounds of reason, appropriateness, or moderation

working under unreasonable pressure

an unreasonable restraint of trade

: lacking justification

an unreasonable inference

unreasonableness

ˌən-ˈrēz-nə-bəl-nəs,

-ˈrē-zᵊn-ə-bəl-

noun

unreasonably

ˌən-ˈrēz-nə-blē,

-ˈrē-zᵊn-ə-blē

adverb

Examples of unreasonable in a Sentence

I told him that I wouldn't pay unless he sent me a replacement. Am I being unreasonable? You are entitled to compensation for unreasonable delays.

Recent Examples on the Web

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

However, critics like the American Civil Liberties Union have called the technology unreasonable surveillance. — Kendrick Calfee, Kansas City Star, 14 Oct. 2026 And the sense that Dodge had built something kind of unreasonable and then discovered that nobody tried to stop them. — New Atlas, 14 Oct. 2026 Brady pointed to a legal doctrine known as laches, which can prevent a party from pursuing a claim after an unreasonable delay that prejudices another party. — Gino Vicci, CBS News, 12 Oct. 2026 The factors most closely tied to burnout included unfair treatment, crushing workloads, unclear expectations, poor communication and support from managers, and unreasonable deadlines. — Christos Makridis, The Conversation, 7 Oct. 2026 See All Example Sentences for unreasonable

Word History

First Known Use

14th century, in the meaning defined at sense 1a

Time Traveler

The first known use of unreasonable was in the 14th century

See more words from the same century

Browse Nearby Words

unreason

unreasonable

unreasoned

See all Nearby Words

Cite this Entry

Style

“Unreasonable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unreasonable. Accessed 20 Oct. 2026.

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Legal Definition

unreasonable

adjective

un·rea·son·able

: not reasonable : beyond what can be accepted: as

: clearly inappropriate, excessive, or harmful in degree or kind

an unreasonable delay

an unreasonable restraint of trade

: lacking justification in fact or circumstance

an unreasonable inference

especially : irrational sense b

the agency decision was unreasonable

: not supported by a warrant or by a valid exception to a warrant requirement (as when there is reasonable suspicion) and therefore unconstitutional

the right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated—U.S. Constitution amend. IV

unreasonable

adjective

Synonyms of unreasonable

Examples of unreasonable in a Sentence

Word History

Browse Nearby Words

Cite this Entry

Legal Definition

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